1. Field of the Invention
The present invention relates to an improvement in a back support system that establishes a desired postural position by creating specific sacral pressure and to apparatus that will properly position the sacrum, the pelvis, including the iliac crests, and the supporting neuro-musculo-skeletal system to produce total pelvic stability.
2. Description of the Prior Art
Back pain, in concept and in fact, is not only prevalent in society but is an area of much research and patent activity. Back pain is something many individuals experience at work, at home, and during the trip therebetween. Back pain has many causes, but few cures. The latter is not for a want of trying. Rather, patents on a wide variety of back supports or support systems abound.
For example, the patents can be generally divided in groups including those relating to seat developments, sacral or lumbosacral braces, fixed cushions or supports, and inflatable devices.
The seat development area can be further subdivided into built-in supports, add-on supports, orthopedic seats, back rests, and office chair designs.
Prior to a summary review of these prior efforts, it should be understood that non-pathogenic back pain usually results from the presence of stress or pressure on the neuro-musculo-skeletal system and affected interrelated anatomical structure. Sometimes that stress or pressure is generated internally within the spinal cord. In either case, the resulting stress can be due to inappropriately applied pressure or due to a distorted or damaged spinal column that has existed for varying periods of time, with resulting pain depending on the prior state of the spinal cord. Consequently, in many situations the neuro-musculo-skeletal system can be supported to either relieve or prevent development of unwanted and undesirable spinal pressure.
An early spine support device is described in Epstein, U.S. Pat. No. 1,667,626. A wooden frame is used to mount a series of spring bands that form a curved face. A batting material fills the space between vertical braces and the whole device was covered with fabric. Using adjustable hooks the device was adjustable to accommodate different sized persons. The device has a width about equal to a person's back and is shown being positioned in the lumbar region to provide uniform support over a broad region.
The built-in devices are exemplified by Sopko, Jr. U.S. Pat. No. 3,145,054 and Burton, U.S. Pat. No. 3,501,197. Sopko relates to a portable chair that incorporates a contoured pneumatic cushion which applies pressure to the posterior surface, in the sacroiliac area, and varies the pressure by forward and rearward movement of the occupant against the back supporting pneumatic cushion.
Burton attempts to restrict the body's movement into the back/seat junction area, where the ischial tuberosities of the pelvic girdle wedges into this back/seat area, by incorporating a rigid back/seat element into the seat to prevent such wedging.
The add-on devices include a variety of devices as shown in Weinreich U.S. Pat. No. 4,753,478; Quinton et al. U.S. Pat. No. 4,718,724; Baxter et al. U.S. Pat. No. 4,516,568; Scott U.S. Pat. No. 4,634,176; and Pasquarelli U.S. Pat. No. 2,831,533.
Each of these devices includes a portion that extends across the entire back of the person as seated in the seat. In Weinreich the support is in the form of a pair of tubular cushions. Quinton et al. suggest that it had proved difficult to standardize the location of lumbar support cushions and thus developed a vertically adjustable lumbar support cushion. Baxter et al. disclose a multi-compartment air bladder, including side and center sections, so that air pressure can be applied on selected lumbar and sacroiliac areas of the body. Scott also provided a vertically movable back support, but it has a greater area than that of Quinton et al. Pasquarelli discloses use of a dorso-lumbar curve support in the form of an elongated cushion that applies pressure across the full width of the person's back.
The lumbosacral braces include Rowe, U.S. Pat. No. 4,930,499; Brooks et al., U.S. Pat. No. 4,475,543; Hyman et al, U.S. Pat. No. 4,576,154; Carabelli, U.S. Pat. No. Des. 296,930; and Lampert, U.S. Pat. No. 2,554,337.
Several patents disclose use of a fixed cushion. These include Parrish, U.S. Pat. No. 4,876,755; Snyder et al, U.S. Pat. No. 4,522,447; and the Meares design patent, U.S. Pat. No. Des. 277,316. The cushion used by Parrish is shaped as a capital "I" and supports the cervical, thoracic and lumbar regions. Snyder et al. designed foam cushions with segments having varying degrees of elasticity to provide inversely proportional support for both seating and backrest surfaces with the softest material provided where pressure would be highest.
Meares shows a design for an orthopedic device that provides full sacral pressures. The design patent does not explain how this device works or functions. However, an associated instruction book explains that the device is to be used by a person primarily in a horizontal condition. The device, while constructed from rubber in soft foam rubber, has a hollow interior and the edges are stiffer due to the presence of sidewalls that surround the hollow interior. Thus, the resistance provided by the Meares device is not uniform. The center is softer than the peripheral edges.
To use the Meares device while lying on the floor, the device is placed on the floor and the user then rolls over onto the device. The instructions explain that the device has a wide end and a narrow end with the wide end being positioned so that it points toward the head. When one first gets on the device, the knees are to be bent and the tail bone is to be rocked down toward the floor. This movement is claimed to help position the curve of the sacrum (tailbone) into the curvature or cradle formed in the device.
As shown in the design patent, the device includes two raised portions on the anterior surface and a flat rear or posterior surface. Because the device is molded from soft rubber, and has a hollow interior, a wider cradle area is formed between the two raised areas.
The Meares device is about 7.25 inches long and has a width of 2.75 inches at the top and about 1 inch at the bottom. The upper raised area extends for about 2 inches, the cradle area then extends for another 3.25 inches with the lower raised portion extending for about 0.75 inches. Thereafter the device slopes toward the narrow end. The device should be used on a firm surface and the instructions suggest that a book could be used if the person was bedridden or a piece of plywood could be positioned under the hips to provide the feeling of a firm support.
The Meares instruction materials also state that his device can be used in a car, truck or a straight back chair. To use the Meares device in such a situation the rubber device is bent into a curved shape and then it is placed both under and slightly behind the person. The instructions also state the seat cushion is soft, a bendable book could be inserted under the rubber device to increase lift. The bent member should cradle the sacrum as when the device was used on the floor.
Thus, Meares suggests, indeed requires, full sacral pressure that is not adjustable with respect to the intensity of pressure being applied. Meares preference is to create constant pressure while the user is in a supine position.
It is also important to note that Meares isolates pressure along the full length of the sacrum. This is intended to provide a treatment to an injured set of muscles, with the piriformis and psoas muscles being of primary concern. Meares' desire is to literally move the whole of the sacrum upwardly (when lying down--movement is toward one's front). If the sacrum can be moved that way, and the hips are allowed to move in the opposite direction, that is, in a sense, to fall downwardly over the sides of his device, both the piriformis and psoas muscles will be stretched to relieve muscle spasms.